摘要
传统的电路模拟吸波材料设计只考虑正入射时的吸波性能,当入射角较大,尤其是大于30°时,雷达吸波器的吸波效果明显恶化。随着现代双站雷达探测技术的发展,雷达探测电磁波可能来自不同的空间方向,这就要求雷达吸波材料不仅在电磁波正入射时具有较高的吸波性能,在斜入射时同样实现良好的隐身特性。为此,该文提出了一种新型的宽带吸波材料。该材料由嵌入集总电阻的导电方环阵列和设计良好的宽角阻抗匹配(WAIM)层组成。由于WAIM层的存在,斜入射情况下的吸波性能明显改善。同时,针对电磁波正斜入射情况,该文提出了准确的等效电路模型以及严格的数学计算模型,使得结构设计清晰明了。测量结果表明,正入射时的吸波带宽达到137.1%。当入射角小于45°时,所设计吸波材料在反射系数衰减至少10 dB情况下的公共百分比吸波带宽达到110.5%。等效电路模型计算、仿真与实测结果之间的相似性验证了该文设计的有效性。
Most previous circuit analog absorbers only considered absorption performance under normal incidences,leading to bad absorption for large incident angles,particularly those>30°.With the advancement in modern bistatic radar detection technology,radar electromagnetic waves may come from different spatial directions,thereby necessitating radar absorbers with high absorption performance under normal and oblique incidences.Thus,in this paper,we present a novel wideband absorber comprising a conductive square-loop array embedded with lumped resistors and a well-designed Wide-Angle Impedance Matching(WAIM)layer.Results show that the WAIM layer can significantly improve absorption under oblique incidences.To make the absorber design clear and simple,an Equivalent Circuit(EC)and strict calculating formulas are proposed under normal and oblique incidences.Fractional bandwidth is increased into 137.1%through measurement under normal incidence,and the structure has a common fractional bandwidth of at least 110.5%for at least 10 dB reflection reduction when the incidence angle<45°.The similarity among EC calculated,simulated,and measured results proves the validity of the designed absorber.
作者
姚智馨
肖绍球
YAO Zhixin;XIAO Shaoqiu(School of Physics,UESTC,Chengdu 611731,China;School of Electronic and Information Engineering,Sun Yat sen University,Guangzhou 510275,China)
出处
《雷达学报(中英文)》
CSCD
北大核心
2021年第2期274-280,共7页
Journal of Radars
基金
国家自然科学基金(61731005)
中央高校基础研究基金(ZYGX2016Z008)。
关键词
电路模拟吸波材料
方环频率选择表面
等效电路
斜入射
宽带宽角吸波
Circuit analog absorber
Square-loop frequency selective surface
Equivalent circuit
Oblique incidence
Ultra-wideband and wide-angle absorption